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111.
Hiro Matsuda Hachiro Nakanishi Shin-Ichi Kato Masao Kato 《Journal of polymer science. Part A, Polymer chemistry》1987,25(6):1663-1669
Poly-1,4-bis(3-acetamidephenyl)-1,3-butadiyne, i.e., a topochemically obtained polydiacetylene for which one can expect π-conjugation between polymer backbone and substituents, has been examined as a candidate of conducting polymers. Upon iodine doping, the polymer film attained the conductivity of 4.8 × 10?2 S/cm, i.e., about three orders of magnitude greater than those of other polydiacetylene films which have no such π-conjugation. 相似文献
112.
Arimoto Y Ohkoshi S Zhong ZJ Seino H Mizobe Y Hashimoto K 《Journal of the American Chemical Society》2003,125(31):9240-9241
A new type of cyano-bridged Co-W bimetallic assembly, CsI[{CoII(3-cyanopyridine)2}{WV(CN)8}].H2O was synthesized. This compound exhibited a temperature-induced phase transition and a photoinduced magnetization. Irradiating with light induced a spontaneous magnetization with a magnetic phase transition temperature at 30 K. This photoinduced magnetization is due to the phase transition from CoIII(LS; S = 0)-WIV(S = 0) to CoII(HS; S = 3/2)-WV(S = 1/2) phases by the irradiation. 相似文献
113.
Ugur Unal Yasumichi Matsumoto Naoko Tamoto Michio Koinuma Masato Machida Kazuyoshi Izawa 《Journal of solid state chemistry》2006,179(1):33-40
Electrostatic self-assembly deposition (ESD) results in the intercalation of Ru(bpy)32+ or methylene blue (MB) into the niobate layered oxide right after the cations come into contact with [Nb6O17]4− nanosheets. Monolayers can be obtained by the exfoliation of proton exchanged K4Nb6O17 (KNbO) in an aqueous tetrabutylammonium (TBA) solution as revealed by the atomic force microscopy micrographs. UV-vis spectra show that intercalated films are able to absorb in the visible light range. Heat-treatment of Ru(bpy)32+ resulted in the red-shift in the absorption spectra, which was assigned to the enhancement in the interaction between the complex molecules and [Nb6O17]4− host layer. Intercalated niobate layered oxides are able to produce photocurrent as a result of the electron transfer from the excited guest molecule to the host layer under visible light illumination. Ru(bpy)32+ intercalated niobate layered oxide shows photocatalytic activity under visible light illumination to produce H2 from water-methanol solution. 相似文献
114.
Ranganathan Kandasamy Masanobu Yamanaka Yasukasu Izawa Sadao Nakai 《Optical Review》2000,7(2):149-151
Using Jones matrix formulation, the theoretical calculations of birefringence compensation technique for a quarter-wave plate scheme are presented. This scheme was proposed and experimentally demonstrated by W. A. Clarkson et al. (Opt. Lett. 24 (1999) 820). In the present paper we have theoretically confirmed that using this method, even in principle, complete compensation is not possible. However, it is shown quantitatively that this scheme does makes possible effective compensation for the birefringence in as few as several tens of watts of pumping power region, which is an attractive feature for laser-diode (LD) pumped solid-state laser systems. We also found good agreement between our theoretical calculations and experimental results obtained by W. A. Clarkson et al. For example, from the analysis we show that only < 0.1% loss will be generated by about 10 W of heat deposited in the rod. This corresponds to about 30 W of LD pump power, which may generate from 6 to 10 W output power depending upon the conversion efficiency of type lasers 相似文献
115.
Shin-Ichi Ishikawa Kyozo Suyama Isamu Satoh 《Applied biochemistry and biotechnology》1999,78(1-3):521-533
Removal of radioactive elements from the effluent and waste aqueous solutions is an important problem. In previous laboratory
batch experiments, hen egg-shell membrane (ESM) was stable as an insoluble protein and was very capable of binding heavy metal
ions from aqueous solution. Batch laboratory pH profile, time dependency, and capacity experiments were performed to determine
the binding of uranium (U) and thorium (Th) to ESM. Batch pH profile experiments indicated that the optimum pH for binding
these actinides was approx 6.0 (U) or 3.0 (Th). The adsorption isotherms were developed at pH 5.0 (U) or 3.0 (Th) at 25°C,
and the adsorption equilibrium data fitted both Langmuir and Freundlich models. The maximum uptakes by the Langmuir model
were about 240 mg U/g and 60 mg Th/g dry weight ESM. In addition, their adsorption capacities increased as salt concentration
increased. ESM could also accumulate uranium from dilute aqueous solution by adjusting to the optimum pH. These results showed
that ESM was effective for removing actinides from solution and would be useful in filtration technology to remove actinides
from aqueous solution.
S.-I. Ishikawa is a research fellow at the Japan Society for the Promotion of Science. 相似文献
116.
Keiji Nagai Qincui Gu Yuzuri Yasuda Takayoshi Norimatsu Shinsuke Fujioka Hiroaki Nishimura Noriaki Miyanaga Yasukazu Izawa Kunioki Mima 《Journal of polymer science. Part A, Polymer chemistry》2009,47(18):4566-4576
A series of tin‐doped hydroxypropyl cellulose (HPC) lyotropic liquid crystal (LC) was synthesized using a simple process and their properties were characterized using selective reflection, wide‐angle X‐ray diffraction (WAXD), and the band texture observed under polarized optical microscope. The present preparation is applicable for mass production using large substrate with low cost HPC. A cholesteric lyotropic LC phase was observed for the hybrid solution with higher than 40 wt % HPC. After sol–gel condensation, the HPC‐Sn hybrid LC films were calcined at 400 °C and the as‐prepared product was determined to obtain tin dioxide (SnO2) which was characterized using WAXD. The iridescent color and ~2 nm structure seen after the condensation disappeared in the as‐prepared SnO2. Scanning electronic microscope images of the SnO2 showed that the HPC content in the HPC‐Sn hybrid played an important role in controlling the SnO2 morphology. A spectrum of relatively monochromatic extreme ultraviolet (13.5 nm) emission was measured in the as‐prepared SnO2 in comparison with bulk tin and inverse opal SnO2. © 2009 Wiley Periodicals, Inc. J Polym Sci Part A: Polym Chem 47: 4566–4576, 2009 相似文献
117.
118.
A newly designed jet-type, water-cooled heat sink (the funryu heat sink, meaning fountain flow in Japanese) yielded 255-W cw laser output at 808 nm from a 1-cm bar made from InGaAsP/InGaP quantum-well active layers with a 67% fill factor [70 quantum-well laser diode (LD) array along the 1-cm bar]. A funryu heat sink measuring 1.1 mm in thickness gave the LD 0.25 degrees C/W thermal resistance, one of the lowest values achieved with a 1-cm LD bar. Over a short period of operation, the device reached a maximum cw power of 255 W. To the best of our knowledge, this is the highest power ever achieved in 808-nm LD operation. In the future, the funryu heat sink may be capable of 80-W cw operation over an extended lifetime of several thousand hours. 相似文献
119.
Izawa K Nakajima Y Goryo J Matsuda Y Osaki S Sugawara H Sato H Thalmeier P Maki K 《Physical review letters》2003,90(11):117001
The superconducting gap structure of recently discovered heavy fermion superconductor PrOs4Sb12 was investigated by using thermal transport measurements in magnetic field rotated relative to the crystal axes. We demonstrate that a novel change in the symmetry of the superconducting gap function occurs deep inside the superconducting state, giving a clear indication of the presence of two distinct superconducting phases with twofold and fourfold symmetries. We infer that the gap functions in both phases have a point node singularity, in contrast to the familiar line node singularity observed in almost all unconventional superconductors. 相似文献
120.
Kosaka W Nomura K Hashimoto K Ohkoshi S 《Journal of the American Chemical Society》2005,127(24):8590-8591
In this work, we observed a spin-crossover phenomenon in a cesium iron hexacyanochromate, which is a Prussian blue analogue. This compound showed a thermal phase transition with transition temperatures of 211 K (T1/2 downward arrow) and 238 K (T1/2 upward arrow) due to a spin-crossover on FeII sites. This spin-crossover phase transition is accompanied by a lattice contraction of 0.38 A, but maintains a face-centered cubic structure (F3m). This is the first observation of FeII spin-crossover in a series of Prussian blue analogues. 相似文献